The present invention relates to precursor compositions for forming ferroelectric, methods for manufacturing precursor compositions, methods for manufacturing ferroelectric films, piezoelectric elements, semiconductor devices, piezoelectric actuators, ink jet recording heads, and ink jet printers.
Ferroelectric materials including PZT are used in various applications, such as, ferroelectric memories, piezoelectric elements, infrared ray sensors, SAW devices, and the like, and their research and development are actively conducted.
A chemical solution method (CSD: Chemical Solution Deposition Method), such as, a sol-gel method and an MOD method is known as a typical method for forming ferroelectrics.
In the sol-gel method, a solution of precursor in which a compound such as metal alkoxide is polymerized through hydrolysis and polycondensation (which is also referred to as “hydrolysis-condensation”) is used. The sol-gel method has an advantage in that the compositions of ferroelectric to be obtained can be controlled well by controlling the compositions of metal alkoxide solution, but has a difficulty in that, because the hydrolysis-condensation reaction is an irreversible reaction, a material that has once been cross-linked and polymerized cannot be used as a sol-gel raw material. In particular, in the case of ferroelectric that includes lead such as PZT, a lead waste treatment needs to be conducted.
Also, in the metal organic decomposition method (MOD: Metal Organic Decomposition Method), a solution of a stable organometallic compound such as carboxylate of a metal or the like is used. The raw material solution used by the MOD method uses a stable organometallic compound as a raw material, and this method provides advantages in that preparation and handling of the solution composition are easy. Unlike the sol-gel method that forms a compound oxide through hydrolysis and polycondensation of a compound, the MOD method forms a compound oxide by resolving an organic group with a large molecular weight in an oxygen atmosphere, and thus has a tendency in which the crystallization temperature is high, and crystal grains would likely become large, compared to the sol-gel method.